The jugular venous pressure (JVP) is an indirect marker of right atrial pressure , reflecting central venous pressure (CVP) . It is clinically observed via the internal jugular vein (IJV) due to its anatomical continuity with the superior vena cava and right atrium .
Why JVP Matters
- Elevated JVP = Right-sided heart pathology
- Decreased JVP = Hypovolemia or distributive shock
- JVP provides valuable information about volume status , right heart function , and cardiac pathology
Anatomical Basis
- The right internal jugular vein is preferred for assessment as it directly drains into the SVC.
- The external jugular vein is more visible but less reliable due to valves and indirect drainage.
- The left IJV is less ideal due to compression by thoracic structures.
Normal JVP
- Measured from the angle of Louis (sternal angle) :
Normal JVP ≤ 3–4 cm above the sternal angle
Since the sternal angle is ~5 cm above the right atrium:
CVP = JVP + 5 cm H₂O
How to Measure JVP Clinically
- Positioning : Patient reclined at 45° angle, head turned slightly left
- Lighting : Use tangential lighting to observe pulsations
- Landmark : Locate the IJV between the heads of the sternocleidomastoid (SCM) and trace toward the earlobe
- Measurement :
- Measure vertical distance from the sternal angle to the top of visible pulsation
- JVP > 4 cm = elevated
Distinguishing JVP from Carotid Artery Pulsation
Use the mnemonic POLICE :
| Feature | JVP | Carotid Pulse |
|---|---|---|
| P alpable | No | Yes |
| O cclusion | Disappears | Persists |
| L ocation | Lateral to carotid, behind SCM | Medial |
| I nspiration | Decreases | No change |
| C ontour | Biphasic | Single beat |
| E rection (Position) | ↓ with sitting, ↑ supine | No significant change |
Hepatojugular Reflex
- Apply pressure to RUQ for ~15 seconds
- Positive sign = Sustained rise in JVP
- Indicates right ventricular failure
Waveform Components of Normal JVP
The jugular pulse has three upward waves (a, c, v) and two downward waves (x, y) :
| Wave | Description | Clinical Correlate |
|---|---|---|
| a wave | Atrial contraction | Just before S1 |
| x descent | Atrial relaxation | During systole |
| c wave | Tricuspid valve bulging during RV systole | Minimal in healthy individuals |
| x' descent | Downward pull of tricuspid | Reflects RV contractility |
| v wave | Passive venous filling during systole | After carotid pulse |
| y descent | Opening of tricuspid, rapid ventricular filling | Follows v wave |
Abnormal JVP Findings and Clinical Implications
1. Raised JVP with Normal Waveform
- Right-sided heart failure
- Fluid overload
- Bradycardia
2. Raised JVP with No Pulsation
- Superior Vena Cava (SVC) Obstruction
- Veins are engorged, non-pulsatile
- Associated with facial edema, cyanosis
3. Large 'a' Wave
- Tricuspid stenosis
- Pulmonary hypertension
- Pulmonary stenosis
4. Cannon 'a' Waves
Occurs when atrium contracts against a closed tricuspid valve :
- Complete heart block
- Ventricular tachycardia
- Atrial flutter with AV dissociation
5. Absent 'a' Wave
- Atrial fibrillation
6. Prominent 'v' Wave (C-V Wave)
- Seen in tricuspid regurgitation
- Continuous rise during systole
7. Slow ‘y’ Descent
- Tricuspid stenosis
8. Kussmaul’s Sign (Paradoxical Rise with Inspiration)
- Constrictive pericarditis
- Pericardial tamponade
- Right ventricular infarction
9. Absent JVP in Hypovolemia
- Common in shock , hemorrhage , severe dehydration
Key Clinical Tips
- Always assess JVP on the right side .
- Use two rulers : one for horizontal distance from the sternal angle, the other for vertical height.
- If not visible:
- Lower the bed to 0° (supine) for low pressures
- Raise to 90° if column is high
